Ice cube making apparatus



OCL 7, 1969 TosHlHlKo AsAKAwA 3,470,709

ICE CUBE' MAKING APPARATUS 4 Sheets-Sheet 1 Filed NOV. 22. 1967 FIG. 7.

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Oct. 7, 1969 Filed Nov. 22, 196'? IIO rosHn-uKo AsAKAwA 3,470,709

ICE CUBE MAKING APPARATUS 4 Sheets-Sheet 2 .2l l l U15 Oct. 7, 1969 Filed Nov. 22, 1967 4 Sheets-Sheet 3 United States Patent O m 3,470,709 ICE CUBE MAKING APPARATUS Toshihiko Asakawa, Osaka, Japan, assignor to Sanyo Electric Co., Ltd., Osaka, Japan, a corporation of Japan Filed Nov. 22, 1967, Ser. No. 684,981 Int. Cl. F25c 1/06 U.S. Cl. 62-347 8 Claims ABSTRACT OF THE DISCLOSURE An ice cube making apparatus in which a plurality of separate ice cubes are formed in a corresponding number of ice cube forming cells which are arranged in a contact relationship with an evaporator and have attached thereto at their respective top and bottom openings mem-y bers defining passages which are continuous to the cells, said members being made of a material having a low heat conductivity, whereby the ice cubes formed in said ice cube forming cells are prevented from being incorporated with those in the respective adjoining cells due to formation of an ice bridge over the top and bottom edges of the Walls defining said ice cube forming cell.

This invention relates to apparatus for forming small pieces of ice and more particularly to apparatus for forming ice cubes for use in restaurants, bars, hotels or similar places in which a large quantity of small pieces of ice is consumed within a short period of time.

One of the conventional ice cube makers is such the type that ice cubes are formed in a vertical freezing tube surrounded by a plurality of bands which are placed in contact and in heat exchange relation with an evaporator, for example, as shown in U.S. patent specification No. 2,775,096 and U.S. patent specification No. 2,549,747. According to this conventional type, the ice cubes formed are of a perforated shape because a plurality of ice cubes must be formed at a time in a freezing tube into which Water is introduced. It is also another disadvantage of the invention that adjoining ice cubes formed in a freezing tube are liable. to be incorporated to each other.

In another conventional device for making ice cubes, an ice plate is first formed on an evaporator dish and then cut into ice cubes by a plurality of heated grid wires, for example, as shown in U.S. patent specification No. 3,230,736. One of the disadvantages of this type that the ice forming position comprising heat grid wires must be additionally arranged as separated from the ice forming position, This will need an additional space and additional equipments, e.g. means for supplying an electric current to the grid Wires. In addition, dangers and troubles in operation will go always with such the ice cube forming device utilizing heat grid wires.

A further conventional type is such that a plurality of invented freezing cells with which an evaporator is in contact are arranged so as to receive water streams from a series of spaced nozzles positioned below the cells. This type is particularly disclosed in U.S. patent specification No. 2,656,686. This type is, however, disadvantageous in that a high pressure pump is required for applying water streams to the downwardly opened cells, that the nozzles must be arranged strictly in relation to the cells, that the ice cubes formed in the cells are liable to be incorporated to those in the adjoining cells over the bottom edges, and that the nozzles for discharging Water streams are liable to be stopped up due to freezing or foreign bodies.

The primary object of the invention is to provide new and improved apparatus for forming ice cubes in which plurality of ice cubes are formed in the respective ice cube forming cells in such a manner that each of the ice cubes can be prevented from being incorporated with any 3,470,705 Patented Oct. 7, 1965 ICC ice cubes formed in the adjoining ice cube forming cell due to formation of ice bridges over the top and botton edges of the walls defining the cell.

Another object of the invention is to provide. new an( improved apparatus for forming ice cubes in which ic| cubes formed in the ice cube cells can be removed fron those cells without diculty.

A further object of the invention is to provide nev and improved apparatus for forming ice cubes whicl can be run continuously without requiring an operato: each time to replenish a cistern with water for ice making even if a suitable source of water such as tap watei usuable as ice making water is hardly obtainable nea; the place at which the apparatus is to be installed; i1 other words, the apparatus can be run at any desire( place of installation without causing any Water shortagt to the cistern.

A still further object of the invention is to provide new and improved apparatus for forming ice cubes whicl includes a water tank in the ice forming chamber so tha` in case that water in the cistern of the ice forming sys tem is not insuicient for the run now going on but i: insufficient for the next run, water may be supplied fron said tank to the cistern after being pre-cooled in sai( tank.

The other objects and features of the invention will bf apparent from the following description of an embodi rnent thereof and the accompanying drawings, in which FIG. 1 is a front view of an ice cube making apparatus embodying the present invention, with one half being shown by cutting oi the front facing;

FIG. 2 is a longitudinal sectional view taken along th( line 2-2 of FIG l;

FIG. 3 is a horizontal sectional view taken along the line 3--3 of FIG. 1 to show the machine chamber o1 the apparatus illustrated in FIGS. 1 and 2;

FIG. 4 is an exploded perspective view of the ice forming apparatus and a refrigerant circuit arrangement foi the apparatus illustrated in FIGS. 1 and 2;

FIG. 5 is a perspective view, on an enlarged scale, 01 a skirt member attached to the ice cube forming cell a1 its bottom;

FIG. 6 is a longitudinal sectional view of the freezer and the Water distributor on an enlarged scale;

FIG. 7 is a longitudinal sectional view on a further enlarged scale of a part of the combination of the freezer and the water distributor illustrated in FIG. 6;

FIG. 8 is a fragmental perspective view, on an enlarged scale, of the evaporator with ice cube forming cells;

FIG. 9 is a longitudinal sectional View of an enlarged scale of the cistern illustrated in FIG. 2;

FIGS. 10 and ll show alternative connections of water supply control meansattached to the cistern with twc water supply sources; and

FIG. 12 shows an electric circuit of the electrically operative system of the apparatus of the invention.

Referring to the drawings, particularly to FIGS. 1 and 2, there is disclosed the ice cube maker of the present invention which includes an ice making chamber 21 and a machine chamber 22 below the ice making chamber 21. The ice making chamber 21 and the machine chamber 22 have two common side wall plates 23, 24 and a common back wall plate 25 and form a vertically elongated square casing generally indicated as 26. The top and bottom ends of the casing 26 are covered by a top cover plate 27 and a bottom cover plate 28. The upper portion of the front end of the ice making chamber 21 is covered by a front wall plate 29, while the lower portion of the front end of the chamber 21 is provided with an opening 30 for an ice storage drawer 31. 32 is the partition wal] between the ice making chamber 21 and a machine chamber 22.

The ice making chamber 21 is defined by an inner liner 53 and includes a cistern 34, a cube forming apparatus 55, a water tank 36 and the ice storage drawer 31. The :istern 34 is located below the cube forming apparatus 55 and the water tank 36 is located in front of the cube orming apparatus 35. The ice storage drawer 31 is nserted through the opening 30 and located below the vater tank 36 and in front of the cistern 34. Between he inner liner 33 and each of the top cover plate 27, vhe side wall plates 23 and 24, the back wall plate 25 tnd the partition wall 32 is interposed heat insulating md preferably hard material 37 such as polyurethane bam. The heat insulating material 37 is also interposed )etween the front cover plate 29 and the front wall 36a of he water tank 36. The cistern 34 has a water pump 38 ,herein for supplying water from the cistern 34 to the cube orming apparatus 35 through a pipe 39. Intermediate )etween the cube forming apparatus 35 and the cstern 54 is located an ice-water separator 40. 41 is exible pipe 'or supplying water from the water tank 36 to the cistern i4. The pipe may be made of polyvinyl chloride. The )pening 30 for the drawer 31 is defined by a square rame 42. 43 is a knob for the drawer 31.

Referring to FIGS. 1, 2 and 3, disposed in the machine :hamber 22 are a refrigerant compressor 44, a condenser l for condensing hot gas discharged from the compressor L4, a motor fan 46 (FIG. 3) for compulsorily cooling he refrigerant compressor 44 and condenser 45, etc. A train tank 47 for receiving drain water from the ice naking chamber 21 through the pipe 48 is removaby nounted near the front opening of the machine chamber 52. The front opening of the machine chamber 22 is tdapted to be closed and opened by means of a cover )late 49 bored with a number of Ventilating holes or :lots 50.

The cube forming apparatus 35 for freezing water tupplied from the cistern 34 and then forming a number f regularly shaped lumps or cubes of ice is illustrated in etail in FIGS. 2, 4, 5, 6 and 7. It comprises a freezer 51 1nd a water distributor 52. The freezer 51 includes a flat :vaporator tube 53 in which refrigerant passages 54 are iormed. The evaporator tube 53 is bent in a serpentine xhape in such a manner that several straight portions 55 tre arranged with regular spaces and in parallel relationrhip to each other. A plurality of cube forming cells 56 1re mounted and arranged in series in each of the spaces Jetween the straight portions 55.

As shown in FIGS. 4, 6, 7 and 8, the cube forming :ell 56 is a square frame of aluminum or other metal raving a high thermal conductivity and is open at its op and bottom. The cell 56 is defined by two opposed /ertically extending Walls 58 which are in intimate con- :act with the straight portions 55 of the evaporator 53 and mother two opposed vertically extending walls 59 per- Jendicular to the walls 58. The walls 58 are fxedly nounted to the straight portions 55 of the evaporator 53 1s by a metal solder. Each of the mounting walls 58 has extensions 60 at its opposed ends. Those extensions 60 unction as spaces and cooperate with the free walls 59 :o form spaces 61 between each adjoining two cube formng cell 56. In this manner, a plurality of cube forming :ells 56 are arranged in series in a spaced relationship netween adjoining two straight portions 55 of the evaprator 53. The cooling power is first transmitted from :he evaporator 53 to the mounting walls 5S but there s not much difference in temperature between the mountng walls 58 and the free walls 59 since the whole cells S6 is formed of a material having a high thermal conluctivity whereby substantially uniform cooling effect is tssured at all the walls 58 and 59. Another advantage of rse of the cube forming cells 56 which are separate `bodies from the evaporators 53 lies in the fact that rough surface )f the evaporator 53 will be no adverse effect in the pro luction of ice cubes since ice is produced in the cells 56. l`he only condition required is to make the inner surface 3f each of the walls 58 and 59 flat and smooth.

In order to prevent ice cubes formed in the cells 56 to be joined to each other over the top edges each of the evaporator tube 53 and the walls 58 and 59, a latticed member 62 is disposed on the top of the freezer 51. The latticed member 62 is made of a heat insulating material having a very low heat conductivity, e.g., ABS resin (acrilate butadiene stylene) and has a plurality of substantially square through holes 63 which communicates with the ice forming cells 56, respectively. Each of the through holes 63 is defined by a pair of two opposed walls 64 and 65. The wall 64 extends in the direction of a straight portion 55 of the evaporator 53 while the wall 65 extends in the direction of the walls 59 of the cube forming cell 56. The through hole 63 is of a double square truncated cone shape having its narrowest horizontal section 66 intermediate between the top and bottom. The bottom opening of the hole 63 is not larger than the top opening of the cell 56. Preferably, the inner surface of each of the walls 64 is substantially continuous with the inner surface of each of the walls 58 of the cube forming cell 56 and the inner surface of each of the walls 65 is substantially continuous with the inner surface of each of the walls 59 of the cell 56, but there may be a step at the junction of the wall 64 or 65 of the hole 63 with the wall 58 or 59 of the cell 56. Each of the walls 65 of the hole has at its bottom end a projection 67 downwardly extending therefrom. The projection 67 is fitted into the space 61 formed between adjoinig two cells 56. In this manner alignment of the holes 63 and the cells 56 can be secured.

In order to prevent ice cube formed in the cells 56 to be joined to each other over the bottom edges each of the evaporator tube 53 and the walls 58 and 59, a skirt or hood member 68 is attached to the bottom end of each of the cube forming cell 56.

The skirt or hood member 68 is made of a heat insulating material having a low heat conductivity, eg. ABS resin (acrylate butadiene stylene) and shaped in a square truncated cone having the largest horizontal section at its bottom opening. The top opening of the skirt member 68 is not smaller than the bottom opening of the cell 56. Preferably, the walls 58 and 59 of the cell 56 are substantially continuous with the corresponding walls of the skirt member 68, respectively, but there may be a step at the junction of the cell 56 and the skirt member 68. The skirt member 68 is provided at its top end with a pair of upwardly extending projections 69 and a pair of laterally extending projections 70 as shown in FIG. 5. The upwardly extending projections 69 are fitted into the space 61 between each adjoining two cells 56 so that alignment of the cells 56 and the skirt members 68 may be secured. The laterally extending projections 70 are snapped in grooves 71 formed evaporator tube 53 along the bottom edge thereof.

Since the lattice member 62 `on the top of the freezer 51 and the skirt members 68 attached at the `bottoms of the cube forming cells 56 are made of heat insulating material, ice is scarcely grown in the holes 63 and in the skirt member 68. If any freezing occurs in the holes 63 and the skirt members 68, the ice formed thereat will be a very thin lm which can be soon melt upon the ice cube removing operation with hot gas passing through the evaporator tube 53. In addition, the combination of the through hole 63, the ice forming cell 56 and the skirt member 68 forms a continuous passage with its horizontal sectional area decreased toward above and increased toward below as a whole so that the ice cube formed in the cell 56 may easily leave the cell 56 and fall down by its own weight.

The lattice member 61 has a surrounding edge 72 upwardly extending from the height of the plane of the top openings of the holes 63 and an overow opening 73 at a lateral plane extension 74 formed at the height of the plane of the top openings of the holes 63 so that water may overliow through the opening 73 when all the cells 56 are stopped up by ice grown therein.

According to the invention, a water distributor 52 is mounted on the top of the lattice member 62. The water distributor 52 is a square shallow vessel the top opening of which is closed `by a cover 'plate 75. The bottom wall 76 is perforated with a number of orifices 77 in alignment with outwardly inclined top edges 78 of the walls 64 and 65 defining the through holes 63 of the lattice member 62 so that water leaving the orifices 77 may drip along the inner surfaces of the walls 64 and 65 of the holes 63. The portion 76a of the bottom walls 76 corresponding to the central portions of the through holes 63 of the lattice member 62 are upwardly stepped to achieve reinforced of the bottom wall 76 and uniform distribution of water to all the orices 63 with the passages 79 running longitudinally and laterally. The number of orifices 63 may be several per each through hole 63. The cover plate 75 functions as a deector to participate in uniform distribution of water. The water distributor 62 is formed at the height of the stepped portions 76a with a lateral plane extension 80 which is provided with a water supply port 81 communicatively connected through a hollow pipe 39 (FIG. 1) to the delivery port of the Water pump 38 in the cistern 34.

Referring back to FIG. 2, the ice-water separator 40 located intermediate between the cube forming apparatus 35 and declivous with a gentle slope toward the ice cube storage drawer 31 as shown in FIG. 2. The ice-water separator 40 mounted on the top opening 32 of the receiver 83 is also inclined in the same direction. The cylindrical portion 84 which is connected to the bottom end of a conical portion 85 having the top opening 82 extends downwardly with its bottom end opening 86 being extended into the cistern 34. The ice-water separator 40 is provided near its front end with at least one drip edge 87 downwardly extending from the water separator 40 so that any water which might ow along the meshes of the ice-water separator toward its front and lower end may drip along the edge 87 into the conical portion 85 of the receiver 83. The reference numeral 88 denotes a guide plate or apron extending from the front end of the freezer 51 downwardly and toward a direction fairly within the area the ice-water separator 40 on the top opening 82 of the receiver 83. The guide plate 88 is preferably made of resilient synthetic resin such as polystyrene. A soft and yieldable shield curtain 89 is attached to the lower end 90 of the guide plate 88 in such a manner that the lower end of the curtain 89 touches or approaches the ice-water separator 40 near its front end, so that the drops of water tending to jump forward can be prevented from such jumping and allowed to flow into the water receiver 83. The ice cubes which have been deposited on the ice-water separator 40 and then fall along the slope of the ice-water separator 40 push aside the curtain S9 to water into the ice cube storage drawer 31. With use of the curtain 89 there is obtained a thermal shielding effect between the lower portion the ice forming apparatus 35 and the front region having a relatively high temperature in the interior the ice making chamber 21, thus preventing the circulating water from increasing in temperature as it contacts with the hot outer air, so that there is no lowering of the efficiency of ice making.

As shown in FIGS 2 and 9, the cistern 34 is formed with a cylindrical holder portion 91 by vertically cylindrically penetratingr and bulging a suitable portion of the bottom wall 92 of the cistern 34. Penetrating through and supported by the cylindrical holder portion 91 is a water supply pipe 93 for connection to a source of water outside the casing 26. The pipe 93 is made of a flexible material such as polyvinyl chloride. The reference numeral 94 in FIG. 2 denotes the connecting end of the water supply pipe 93 to which a hose (not shown) is connected. The hose is then connected to a suitable water supply source, With the provision of such the holder portion 92 there is no need of additionally providing means for holding said water supply pipe 93, so that the steps of manufacture are reduced and facilitated. Moreover, if the upper end 95 of the holder portion 91 is open below the upper end of the peripheral walls 93 of the cistern 34, the opening 95 may serve as an overflow port in the event that too much water enters the cistern 34. It should, therefore, be noted that the inner diameter of the folder portion 91 is larger than the outer diameter of the pipe 93 so that there may be a clearance or gap forming an overflow passage between the holder portion 92 and the pipe 93. The cistern 34 is provided at its lower end with a drain opening 97 which is closed by a removable plug 98.

The ice cube maker embodying the invention is provided with two systems for supplying water which are simple in construction and easy to handle. These two systems are alternatively used. One of the systems is such that where a suitable supply source of water such as tap water is available, the one end 94 of water supply pipe 93 is connected to the supply source of water outside the casing 26 and the other end opening 95 is connected to the suction port 99 of a water supply control means 100 by means of a joint 101 as shown in FIG. l0. The suction port 99 of the control means 100 communicates with the delivery port 102 opened within the cistern 34. Cornmunication of the suction port 99 with the delivery port 102 is normally ilacked by a valve body (not shown) which is actuated by energization of an electromagnetic coil 103 which will be described in detail hereinafter with reference to FIG. l2. The level of water in the cistern is sensed by a water-level sensing means 104 (FIG. 2) and the movement of the sensing means 104 results in excitation of the electromagnetic coil 103 for establishing the communication of the suction port 99 with the delivery port 102, whereby water in the supply source of water is supplied to the cistern 34.

The other system for supplying lwater is used where no suitable source of water is available at the cite of installation of the ice cube maker of the invention or such source of water is inferior in quality. The alternative system comprises a relatively large water tank or reservoir 36 and a water supply pipe 41 connected to the bottom of the tank 36. The water tank 36 is provided at its top with a water supply port 105 which is normally closed by a removable cover 106. The water tank 36 stores therein clean water introduced through the supply port 105. The suction port 99 of the control means 100 is connected to the free end of the supply pipe 41 extending from the water reservoir 36, with the end opening 106 (FIG. 11) of the supply pipe 93 in the other system being removed from the joint 101, as shown in FIG. ll. Since the water tank 36 is positioned between the ice forming apparatus 35 and the front cover plate 29, there is no useless space left in the ice making chamber 21 and, moreover, since water in the reservoir 36 will be pre-cooled under the influence of the ice forming apparatus 35, the eiciency of ice making is increased and this also contributes to the thermal shielding, thus lessening the formation of dewdrops on the outer surface of the front cover plate 29. The simultaneous provision of two water supplying systems such as mentioned above allows the user to effect ice making operation at any desired place without being restricted by the place of use, thus remarkably improving usability.

Still referring to FIG. 2, the ice cube storage drawer 31 has a packing 107 provided around the peripheral edge of the inner surface of the front wall 108 in such a manner that when the ice storage drawer 31 is received in the ice making chamber 36, the packing 107 abuts against the front surface of the frame body 41 located below the front wall plate 29 thereby to effect thermal shielding between the interior of the ice making chamber 21 and the outer air. At a suitable place in the rear portion of the bottom plate 108 of the drawer, there is bored a through aperture 109 for draining the water resulting from the melting of the cubes of ice stored in the drawer. A wiper member 110 of a flexible material mounted on the bottom wall of the inner liner 33 is contacted with the outer surface of said bottom wall 108 to wipe away any dewdrops adhered to the outer surface of this bottom wall so as to prevent the dewdrops from flowing out when the ice storage drawer 31 is drawn. During normal use of the ice cube storage drawer 31, even if it is drawn to a maximum degree, the drain through aperture 169 remains inside of the wiper member 110.

A temperature sensing element 111 is located within the drawer 31 near its top opening. The temperature sensing element 111 is mounted on the free end of a support bar 112 extending from the front edge of the top opening 82 of the water receiver 83 toward the inside of the drawer 31. At the top end of the rear wall 113 of the drawer 31, there is formed a cutout 114 which allows the temperature sensing element 111 to leave the outside of the drawer 31 through the cutout 114. The temperature sensing element can thus detect the level of the ice cubed in the drawer 31. Any response at the heat sensing element 111 according to the temperature of the ice cubes in the drawer 31 is transmitted by means of a capillary 121 (FIG. 1) filled with fleon gas to a temperature control switch (not shown in FIG. l but indicated as 123 in FIG. l2) in a control box 117 disposed in the machine chamber 22. Thus, as soon as the temperature sensing element 111 touches the ice cubes, the switch 123 is opened to step all the operations before the ice storage drawer 31 becomes overbrimming with lumps of ice.

Another heat sensing means 124 is mounted on the freezer 51 as shown in FIG. 1. Any response at heat sensing means 124 according to the temperature of the freezer 51 is transmitted by means of a capillary 12S filled up with fleon gas to a temperature control switch (not shown in FIG. l but indicated as 126 in FIG. 12) in the control box 117. The contr-ol switch 126 makes and breaks the electrical circuit for controlling the ice forming operation and the ice cube removing operation. The reference numeral 118 in FIGS. 2 and 4 denotes an electromagnetic valve which allows hot gas discharged from the compressor 44 to be introduced directly to the evaporator 53 through a bypass 119 on the ice cube removing operation. The reference numeral 12d in FIG. 4 indicates a receiver connected to the evaporator 53.

Referring to FIG. l2, an electric motor 122 for the refrigerant compressor 44 is connected to a source of voltage 127 through the temperature switch 123 actuated by the temperature Sensing element 111 and a main switch 128. The' reference numeral 128 indicates an electric motor for the water pump 38 and the reference numeral 129 indicates an electric motor for the fan 46. These two motors 128 and 129 are connected in parallel relation to the source of voltage 127 through the temperature control switch 126 actuated by the temperature sensing means 124. A solenoid 130 for actuating the electromagnetic valve 118 is connected in series to each of the motors 128 and 129 and in parallel to the temperature control switch 126. A series circuit including a switch 131 and the electromagnetic coil 103 for the water supply control means 100 is connected in parallel to each of the solenoid 130 and the temperature control switch 126 and in series to the water pump motor 128. The impedance of the switch magnet valve solenoid 13G is much greater than the resultant impedance of the water pump motor 128 and the fan motor 129, t0 such the degree that the latter impedance is negligible during the ice cube removing operation. The actual test showed that the ratio was 10:1 during the ice cube removing operation alone and :1 during lthe simultaneous ice cube removing and water supplying operation. Therefore, if the temperature control switch 125 is in a closed position, the solenoid 130 is not energized but the' water pump motor 128 and the fan motor 129 are driven for the ice making operation and if the temperature control switch 126 is in an opened position, the switching magnet valve solenoid 131) is energized to deliver the hot gas to the ice cube forming apparatus 35 through the by-pass pipe 119 so as to melt the surfaces of the lumps of ice frozen and formed by the ice cube forming cells S6, thereby removing the ice cubes from the cells 56. At this time the water pump 38 and the fan 46 are in substantially stopped conditions. Further, if the switch 131 of the water-level sensing means 104 is in a closed position, the solenoid 103 of the water supply control means is energized so that water is supplementally fed to the cistern 34 either from the outside source of water through the water supply pipe 93 or from the water tank or reservoir 36. With the circuit thus arranged, only one temperature sensing element 111 suices for the ice making operation ice cube removing operation and water supplying operation, thus contributing to the simplification of the apparatus and of wiring work as well as minimizing the danger of causing troubles. Further the possibilities of supplemental water supplying operation taking place of hot gas flowing to the ice forming section during supplemental water feeding operation are precluded.

As shown in FIGS. 2 and 3, the motor fan 46 is placed at a corner position of the machine chamber 22 so as to air-cool the refrigerant compressor 44 and the condenser 134. The reference numeral 135 denotes a protector plate having a number of Ventilating holes 136 for preventing the users fingers, etc. from touching the fan 46 when he replaces or removes the drain tank 47, and also to serve as a lateral guide at that time of replacement or removal of the drain tank 47. The drain tank 47, which receives the water flowing out through the pipe 48 from a drain port 137 (FIG. 2) formed in the bottom wall of the inner liner 33, is partially cut oif at the corner portion 138 (FIG. 3) so that the wind produced by the fan 46 is not obstructed.

While details of the present invention have been described with reference to an embodiment thereof, various variations in details including, for example, the continuous and integral formation of the ice cube forming cells 56 and the skirt members 68 may easily be achieved by those skilled in the art and should, of course, be including in the scope of the appended claims.

What I claim is:

1. In ice cube making apparatus, the combination of, a freezer for forming ice cubes, said freezer comprising a flat, evaporator tube elongated in a serpentine form having a plurality of straight extending portions which are arranged with regular spaces and in parallel relation to each other, said evaporator tube having at least one refrigerant passage, and a plurality of ice cube forming cells which are mounted and arranged in series in each of the spaces between said straight extending portions, each of said ice cube forming cells being formed of material having a heat conduct-ive material in a square frame shape which is defined by four vertically extending fiat walls and has openings at its top and bottom ends; a latticed member mounted on the top of said freezer, said latticed member being made of a heat insulating material and having a plurality of substantially square through holes which communicates with said ice cube forming cells, respectively, the bottom opening of said through hole being not larger than the top opening of said ice cube forming cell; skirt members attached to said ice cube forming members at their respective bottom openings, each of said skirt member being made of a heat insulating material and shaped in a square truncated cone having a top opening not smaller than the bottom opening of said ice cube forming cell and a bottom opening at which the horizontal section is largest; a water distributor located above said latticed member, said water distributor having orifices through which water is distributed to said through holes of said latticed member, each of said oritices being directed to an inner wall defining said through hole; an ice-water separator located below said skirt members; a water cistern located below said ice-water separator for receiving water separated from ice cubes at said ice-water separator; means for harvesting ice cubes separated from water at said ice-Water separator; and means for supplying water from said cistern to said water distributor.

2. Apparatus as defined in claim 1, wherein each of said through holes of said latticed member is of a double square truncated cone shape having its narrowest horizontal section intermediate between the top and bottom thereof.

3. Apparatus as defined in claim 1, wherein said water distributor -is a square shallow vessel the top opening of which is closed by a cover plate, the bottom wall of said vessel being perforated with said orifices for distributing water therethrough and being upwardly stepped at its portions corresponding to the central portions of said through holes of said lattice member.

4. The combination of claim 1, further comprising an elongated casing formed with an ice making chamber and a machine chamber disposed below said ice making chamber, said freezer being disposed within said ice making chamber, said water distributor being disposed within said ice making chamber above said freezer, said ice water separator being disposed Within said ice making chamber below said freezer, said harvesting means being disposed within said ice making chamber, a water tank disposed within said ice making chamber above said harvesting means, a refrigerant compressor located in the machine chamber, and a condenser for condensing hot gas discharged from said compressor, said condenser being located in said machine chamber, said refrigerant compressor and said condenser cooperating with said evaporator to form a refrigerant circuit.

5. Apparatus as defined in claim 4, further including a water supply line one end of which is connected to a water supply source outside of said casing, a water supply pipe for supplying water from said water tank to said water cistern, and water supply control means for selectively communicating either said water supply line from an outside water supply source or said water supply pipe from said water tank with said water cistern.

6. Apparatus as defined in claim 1, wherein said icewater separator is provided near its front and lowest end with at least one drip edge downwardly extending therefrom.

7. Ice cube making apparatus, comprising an elongated casing forming an ice making chamber and a machine chamber disposed below said ice making chamber, a freezer for forming ice cubes, said freezer including an evaporator tube through which refrigerant Hows, a Water distributor located in said -ice making chamber above said freezer, an ice-water separator located in said ice making chamber below said freezer, a water cistern located in said ice-making chamber below said ice-water separator for receiving water separated from ice cubes at said ice-water separator, means for supplying water from said cistern to said water distributor, storage means for harvesting ice cubes separated from water at said ice-water separator, said storage means being located in said ice making chamber, a water tank located in said ice making chamber above said ice cube storage, a refrigerant compressor located in said machine chamber, a condenser for condensing hot gas discharged from said compressor, said condenser being located in said machine chamber, said refrigerant compressor and said condenser cooperating with said evaporator to form a refrigerant circuit, a water supply line one end of which is connected to a water supply source outside of said casing, a water supply pipe for supplying water from said water tank to said water cistern, and water supply control means for selectively communicating either said water supply line from an outside water supply source or said water supply pipe from said water tank with said water cistern, said cistern being formed with a cylindrical holder portion of the bottom wall of the cistern so that said water supply line connected to an outside water supply source passes through and is supported by said cylindrical holding portion, the top opening of said cylindrical holder portion being located below the top opening of said cistern.

8. Ice cube making apparatus, comprising a freezer for forming ice cubes, said freezer comprising an evaporator tube having at least one extending portion arranged with spaced portions, said evaporator tube having at least one refrigerant passage, and a plurality of ice cube forming cells formed of a heat conductive material with openings at top and bottom ends thereof, a water distributor located above said freezer, said water distributor having orifices through which water is distributed to inside of Walls of said ice cube forming cells; an ice water separator located below said freezer; a water cistern located below said ice water separator for receiving water separated from ice cubes at said ice-water separator; and means for supplying water from said cistern to said water distributor.

References Cited UNITED STATES PATENTS 2,487,408 11/1949 Askin 62.--345 X 2,605,621 8/ 1952 Kellershon 62-344 3,289,430 12/1966 Dedricks et al 62-347 X 3,255,606 6/1966 Hammer 62-353 X 3,357,200 12/ 1967 Connors 62-349 WILLIAM E. WAYNER, Primary Examiner 

